/Engine/Source/Runtime/GeometryCore/Public/TetUtil.h
Test whether point Pt is inside or on a (non-degenerate) tetrahedron Tet. Note: Will always report 'outside' for a fully degenerate (flat) tetrahedron
0 if Pt is outside Tet (or Tet is degenerate), 1 if Pt is inside a positively-oriented Tet, -1 if Pt is inside and Tet is inverted
namespace UE { namespace Geometry { namespace TetUtil { template<typename RealType> int32 UE::Geometry::TetUtil::IsInsideExact ( const [TTetrahedron3](API\Runtime\GeometryCore\TTetrahedron3)< RealType > & Tet, [TVector](API\Runtime\Core\Math\TVector)< RealType > & Pt ) } } }